Anti-fungal seed treatment formulations, treated seeds, and methods

ABSTRACT

A coated seed comprises a seed and a coating at least partially surrounding the seed. The coating comprises a fungicide, a micronutrient metal, and a chelating agent, the fungicide comprising copper (II) hydroxide, wherein the amount of copper (II) hydroxide is from about 0.05 mg/seed to about 0.21 mg/seed. 
     A method for applying a seed treatment to a seed or a population of seeds comprises distributing on the surface of the seed or the population of seeds a seed treatment formulation comprising a fungicide, a micronutrient metal, and a chelating agent. The fungicide comprises copper (II) hydroxide in an amount ranging from about 2 wt. % to about 20 wt. % of the total seed treatment formulation.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application hereby claims the benefit of the utility patentapplication of the same title, Ser. No. 15/878,704, filed on Jan. 24,2018, which claimed the benefit of the provisional patent application ofthe same title, Ser. No. 62/450,020, filed on Jan. 24, 2017, thedisclosures of which are herein incorporated by reference in theirentirety.

BACKGROUND

Aspects of the present disclosure generally relate to seed treatmentformulations, treated (e.g. coated) seeds, and methods of protectingemerging root systems from fungal growth. In particular, embodiments ofthe seed treatments described herein are capable of reducing and/orsubstantially eliminating fungal contaminants from emerging root systemsand the surrounding environment, where such fungal contaminants includebut are not limited to species of Fusarium, Pythium, and Rhizoctonia.

The increasing popularity of spinach among consumers has caused asignificant increase in the amount of spinach grown in the U.S. inrecent years. Persistent pathogenic infection of spinach and other leafygreens in the early stages of development, however, can cause up to a70% loss in yield (see Larsson et al., “Disease progression and yieldlosses from root diseases caused by soilborne pathogens of spinach,”Phytopathology 82:403-406 (1992)), resulting in substantial economicloss for growers and increased food prices for consumers. Specifically,spinach and leafy greens are particularly susceptible to infection by“damping off” complexes and similar root rot diseases, which can causepoor germination and root establishment in infected fields during thefirst week of development. In infected soils, for example, yield maydecrease as the result of desiccation or death of seedlings either pre-or post-emergence, as well as poor overall growth and yellowing ofleaves. Susceptibility to such “damping off” and root rot can beexacerbated by poor field conditions, including overwatering, inadequatedrainage, and/or crowded planting. While various pathogenic speciesfound in soil can cause “damping off” or root rot, the more commonpathogens include fungal species and fungi-like species (oomycetes) ofFusarium, Pythium, and Rhizoctonia. The poor emergence and/or growth ofseedlings due to “damping off” and/or root rot may also affect othercrops, including corn, wheat, potato, and soybean, among others.

In general, control of damping off and root rot has been attempted by avariety of methods. One method that may be employed in an effort toreduce or eliminate damping off is to sow seeds in a sterilized growingmedium; however, such a method may prove ineffective as fungal sporesmay be introduced to the growth medium either on the seeds themselves orafter sowing (e.g. in water or by wind). Methods requiring sterilegrowing environments may also be impractical and/or increase costs,particularly for commercial growers managing significant crop acreage.Further methods to prevent damping off include soil drenches, which arenot economical due to the fast production cycle where time from plantingto harvest is less than 30 days. And, most soil drenches have the addedundesirable requirement of long re-entry intervals before workers arepermitted to return to the fields.

Another method widely used in the agricultural industry to controlfungal infections is the use of fungicides. Fungicides such as metalaxyl(N-(methoxyacetyl)-N-(2,6-xylyl)-DL-alaninate), thiram(dimethylcarbamothioylsulfanyl N,N-dimethylcarbamodithioate), andipconazole(2-[4(chloropheyl)methyl]-5-(1-methylethyl)-1-(1H-1,2,4-trazol-1-ylmethyl)cyclopentanol)have been shown to effectively control fungal infections in emergingroot systems, but such use of conventional applied chemistries renderthese materials unsuitable for the commercial production of organiccrops. Copper (II) hydroxide has also found widespread application inthe agricultural industry as a fungicide and bactericide. Commerciallyavailable in liquid and water dispersible granule form (Champ®,Kocide®), copper (II) hydroxide formulations have, however,traditionally been applied to crop fields by spraying or otherwisecoating the leaf surface (i.e. foliar sprays); that is, applicationoccurs post-emergence. Such a contact fungicide in its typical sprayform is thus ineffective to treat or prevent soil-borne fungalconditions that invade the emerging root system at the early stages ofdevelopment (e.g. in the first week after planting).

Current seed treatments marketed for the prevention of damping off androot rot are available, but suffer from significant drawbacks. For theorganic market in particular, such seed treatment formulations comprisemicrobial species, known as bio-pesticides, which are intended tomitigate the effects of insects or disease. Bio-pesticides can bedifficult to control under constantly changing environmental conditions,including variations in soil and air temperature, humidity, soilmoisture, and nutrient content. The slow growth of these microbialspecies is similarly problematic, as the microbes may not develop in amanner appropriate to outcompete soil pathogens for root colonization.This slow microbial growth is particularly disadvantageous with respectto Pythium and other fungal species, which become established in theemerging root system within just 7 to 10 days after planting.

To address the shortcomings of the methods currently available in theagricultural industry to mitigate or prevent damping off and root rot,it would be advantageous to provide a chemical seed treatmentformulation that combines root development nutrition and root protectionto combat both pre-emergence and post-emergence fungal infection, wherethe seed treatment is suitable for use in organic crop production.

BRIEF SUMMARY

Seed treatment formulations for efficiently and cost-effectivelyprotecting seeds and emerging root systems from fungal infections.

In some embodiments, a coated seed comprises a seed and a coating atleast partially surrounding the seed. The coating comprises a fungicide,a micronutrient metal, and a chelating agent, the fungicide comprisingcopper (II) hydroxide, wherein the amount of copper (II) hydroxide isfrom about 0.05 mg/seed to about 0.21 mg/seed.

In some embodiments, a method for applying a seed treatment to a seed ora population of seeds comprises distributing on the surface of the seedor the population of seeds a seed treatment formulation comprising afungicide, a micronutrient metal, and a chelating agent. The fungicidecomprises copper (II) hydroxide in an amount ranging from about 2 wt. %to about 20 wt. % of the total seed treatment formulation.

In some embodiments, a method of protecting an emerging root system fromfungal infection comprises (i) providing at least one seed, (ii) coatingthe at least one seed with a seed treatment formulation comprising afungicide, a micronutrient metal, and a chelating agent, (iii) dryingthe seed treatment formulation to form a coating, and (iv) planting thecoated seed under conditions suitable for germination. The fungicidecomprises copper (II) hydroxide. The amount of copper (II) hydroxidecomprises at least 2 wt. % and no more than about 20 wt. % of the totalseed treatment formulation

Other aspects and features will be in part apparent and in partdescribed in detail hereinafter.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments, and together withthe general description given above, and the detailed description of theembodiments given below, serve to explain the principles of the presentdisclosure.

FIG. 1 is a photographic image of Halperin Field Trial, viewed fromoverhead of randomized split plots planted with spinach seed treatedwith a seed treatment according to the present disclosure (“CT” and“YT”) and untreated spinach seed (“CR” and “YR”) at six days afterplanting at Halperin, as further described in Example 2.

FIG. 2 depicts an image analysis comparing canopy density of raw (i.e.untreated) Callisto spinach seed to Callisto spinach seed treated with aseed treatment according to the present disclosure, shown at six days(6) after planting at Halperin, as further described in Example 2.

FIG. 3 depicts an image analysis comparing canopy density of raw (i.e.untreated) Callisto spinach seed to Callisto spinach seed treated with aseed treatment according to the present disclosure, shown at ten (10)days after planting at Halperin, as further described in Example 2.

FIG. 4 depicts an image analysis comparing canopy density of raw (i.e.untreated) Callisto spinach seed to Callisto spinach seed treated with aseed treatment according to the present disclosure, shown at fourteen(14) days after planting at Halperin, as further described in Example 2.

FIG. 5 is a graph depicting the percentages of canopy ground coverageover time for Callisto spinach seed planted at Halperin, comparing rawseed and seed treated with the seed treatment in accordance with thepresent disclosure, as further described in Example 2.

FIG. 6 is a graph depicting the percentages of canopy ground coverageover time for Yukon spinach seed planted at Halperin, comparing raw seedand seed treated with the seed treatment in accordance with the presentdisclosure, as further described in Example 2.

FIG. 7A-7F are a series of graphs depicting canopy coverage for raw(i.e. untreated) seed and seed treated with a seed treatment inaccordance with the present disclosure, for two spinach varieties atvarious times after planting at Halperin.

FIG. 8 is a photographic image of Chualar Field Trial, viewed fromoverhead of randomized split plots planted with spinach seed treatedwith a seed treatment according to the present disclosure (“CT” and“YT”) and untreated spinach seed (“CR” and “YR”) at six days afterplanting at Chualar, as further described in Example 3.

FIG. 9 depicts photographic and reverse images of canopy density of raw(i.e. untreated) Callisto spinach seed shown at ten (10) days afterplanting at Chualar, as further described in Example 3.

FIG. 10 depicts photographic and reverse images of canopy density ofCallisto spinach seed treated with a seed treatment according to thepresent disclosure, shown at ten (10) days after planting at Chualar, asfurther described in Example 3.

FIG. 11 is a graph depicting the percentages of canopy ground coverageover time for Callisto spinach seed planted at Chualar, comparing rawseed and seed treated with the seed treatment in accordance with thepresent disclosure, as further described in Example 3.

FIG. 12 is a graph depicting the percentages of canopy ground coverageover time for Yukon spinach seed planted at Chualar, comparing raw seedand seed treated with the seed treatment in accordance with the presentdisclosure, as further described in Example 3.

FIG. 13A-13F are a series of graphs depicting canopy coverage for raw(i.e. untreated) seed and seed treated with a seed treatment inaccordance with the present disclosure, for two spinach varieties atvarious times after planting at Chualar.

DETAILED DESCRIPTION

Aspects of the present disclosure are directed to a seed treatmentformulation for protecting an emerging root system from fungalinfection, as well as a seed coated with the formulation and method ofusing the formulation on seeds. In one aspect, the seed treatmentformulation comprises a fungicide comprising copper (II) hydroxide, amicronutrient metal, and a chelating agent. In a further aspect, thecopper (II) hydroxide is provided in an amount of at least about 2 wt. %to no more than 20 wt. % of the total seed treatment formulation.

Applicants have surprisingly and unexpectedly found that copper (II)hydroxide, a micronutrient metal, and a chelating agent, when combinedin a seed treatment formulation and specifically a seed coating, actsynergistically to combat fungal pathogens and strengthen the emergingroot system. Without wishing to be bound by any theory, it is believedthat the seed treatment formulation is capable of providing protectionagainst fungal species resident in the soil where seeds are planted. Inparticular, in one aspect, the formulation may be capable of both actingas a fungicide as well as promoting root growth to ensure healthy growthof plants from the planted seed, substantially without succumbing tofungal infection. It is further believed that uptake of the anti-fungaland anti-bacterial agent copper (II) hydroxide is significantly improvedby the incorporation of a chelating agent, which both assists in thetransport of copper (II) hydroxide across the fungal cell membrane andimproves absorption of beneficial micronutrient metals by the emergingplant. Accordingly, the formulations provide a means to offensivelyattack the fungal pathogen at a cellular level and strengthen the rootsystem in a manner that allows such root system to better defend againstpathogenic invasion.

A “seed treatment” according to the present disclosure may be defined asapplication of a material to a seed prior to or during the time it isplanted in soil to improve the characteristics of the seed, protect theseed prior to germination, support the germination and/or support thegrowth of the resulting plant. In the embodiments of the presentdisclosure, seed treatments include agricultural active ingredientsbound to (e.g. coated onto) a seed or plurality of seeds. “Treating” asused herein refers to any effect, for example, lessening, reducing ormodulating, that results in the improvement of the condition, disease,disorder, and the like.

The seed treatment formulation may be effective to mitigate (e.g. lessenthe severity of) or prevent a variety of plant diseases and conditions.In particular, the seed treatment formulation may successfully mitigatethe effects of, or even prevent, invasion of an emerging root system byfungal containments. In some embodiments, the seed treatment formulationmay be effective to mitigate or prevent fungal infection of an emergingroot system by one or more species of the following: Alternaria,Botrytis, Fusarium, Macrophomina, Phyllosticta, Phytophthora,Pseudomonas, Pythium, Rhizoctonia, Sclerotium, and/or Thielaviopsis. Inan exemplary embodiment, the seed treatment formulation may be effectiveto mitigate or prevent fungal infection of an emerging root system byone or more species of Fusarium, Pythium, and/or Rhizoctonia. In aparticularly preferred embodiment, the seed treatment formulation may beeffective to mitigate or prevent fungal infection of an emerging rootsystem by Fusarium oxysporum, Pythium ultimum, and/or Rhizoctoniasolani. In yet other embodiments, the seed treatment formulation mayalso effectively mitigate or prevent bacterial infection of an emergingroot system, for example, an infection by the bacterial pathogenPseudomonis syringae.

A coated seed comprises a seed and a coating at least partiallysurrounding the seed. The coating comprises a fungicide, a micronutrientmetal, and a chelating agent, the fungicide comprising copper (II)hydroxide, wherein the amount of copper (II) hydroxide is from about0.05 mg/seed to about 0.21 mg/seed. In some embodiments, the amount ofcopper (II) hydroxide is from about 0.05 mg/seed to about 0.21 mg/seed,such as about 0.055 mg/seed to about 0.21 mg/seed, about 0.06 mg/seed toabout 0.21 mg/seed, about 0.08 mg/seed to about 0.21 mg/seed, about 0.10mg/seed to about 0.21 mg/seed, about 0.12 mg/seed to about 0.21 mg/seed,about 0.05 mg/seed to about 0.19 mg/seed, about 0.05 mg/seed to about0.15 mg/seed, about 0.05 mg/seed to about 0.12 mg/seed, about 0.05mg/seed to about 0.10 mg/seed, about 0.05 mg/seed to about 0.08 mg/seed,and about 0.05 mg/seed to about 0.06 mg/seed.

In general, a seed treatment formulation in accordance with the presentdisclosure comprises a fungicide. In some embodiments, the fungicidecomprises free copper ion (Cu²⁺). In one exemplary embodiment, the seedtreatment formulation comprises copper (II) hydroxide. Commerciallyavailable forms of copper (II) hydroxide that may be employed in thedisclosed seed treatment formulation include, but are not limited to,Champ® WG (Nufarm Ltd., 77% copper hydroxide) and Kocide® 101 (CertisUSA, 77% copper hydroxide). Various concentrations of copper (II)hydroxide may be used in the seed treatment formulation in an amountsufficient to mitigate or prevent fungal infection of an emerging rootsystem. Such amounts may be determined in light of this disclosure andin accordance with methods known to those of skill in the art.

In one embodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount comprising between about 2 wt. % and about 20 wt.% of the total seed treatment formulation. In another embodiment, theseed treatment formulation comprises copper (II) hydroxide in an amountcomprising between about 2 wt. % and about 15 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount comprisingbetween about 2 wt. % and about 10 wt. % of the total seed treatmentformulation. In another embodiment, the seed treatment formulationcomprises copper (II) hydroxide in an amount comprising between about 4wt. % and about 8 wt. % of the total seed treatment formulation. Inanother embodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount comprising between about 5 wt. % and about 7 wt.% of the total seed treatment formulation. In another embodiment, theseed treatment formulation comprises copper (II) hydroxide in an amountcomprising about 5 wt. %, 6 wt. %, 7 wt. %, 8 wt. %, 9 wt. %, 10 wt. %,11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18wt. %, 19 wt. % or 20 wt. % of the total seed treatment formulation. Inanother embodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount no less than about 2 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount no less thanabout 4 wt. % of the total seed treatment formulation. In anotherembodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount no less than about 5 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount no more thanabout 20 wt. % of the total seed treatment formulation. In anotherembodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount no more than about 17 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount no more thanabout 15 wt. % of the total seed treatment formulation. In anotherembodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount no more than about 12 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount no more thanabout 10 wt. % of the total seed treatment formulation. In anotherembodiment, the seed treatment formulation comprises copper (II)hydroxide in an amount no more than about 8 wt. % of the total seedtreatment formulation. In another embodiment, the seed treatmentformulation comprises copper (II) hydroxide in an amount no more thanabout 6 wt. % of the total seed treatment formulation.

In general, the seed treatment formulation comprises a micronutrientmetal source. Suitable micronutrient sources include zinc, manganese,iron, boron, chromium, cobalt, copper, and molybdenum salts such asphosphates, oxides, sulfates, carbonates, chlorides, nitrates, borates,molybdates and the like and mixtures thereof. For example, the followingrepresentative materials may be used as micronutrient sources: zincsulfate, zinc nitrate, calcium sulfate, calcium nitrate, magnesiumsulfate, magnesium nitrate, ferrous sulfate, ferrous nitrate, manganesesulfate, manganese nitrate, copper sulfate, copper nitrate, boric acid,sodium borate, sodium molybdate, ammonium molybdate and the like, eitheralone or in combination. In a preferred embodiment, the micronutrientsource is zinc sulfate.

The seed treatment formulation may be used with all types of seeds. Insome embodiments, the treatment formulation is used with spinach, peas,forage corn, sweet corn, and soybeans. In some embodiments, thetreatment formulation is used with spinach seeds. In some embodiments,the treatment formulation is used with pea seeds. In some embodiments,the treatment formulation is used with forage corn seeds. In someembodiments, the treatment formulation is used with sweet corn seeds. Insome embodiments, the treatment formulation is used with soybean seeds.

In some embodiments, the coated seed is a spinach seed, which comprisesa coating at least partially surrounding the seed. The coating comprisesa fungicide, a micronutrient metal, and a chelating agent, the fungicidecomprising copper (II) hydroxide, wherein the amount of copper (II)hydroxide is from about 0.05 mg/seed to about 0.08 mg/seed.

In some embodiments, the coated seed is a pea seed, which comprises acoating at least partially surrounding the seed. The coating comprises afungicide, a micronutrient metal, and a chelating agent, the fungicidecomprising copper (II) hydroxide, wherein the amount of copper (II)hydroxide is from about 0.1 mg/seed to about 0.21 mg/seed.

In some embodiments, the coated seed is a corn seed, which comprises acoating at least partially surrounding the seed. The coating comprises afungicide, a micronutrient metal, and a chelating agent, the fungicidecomprising copper (II) hydroxide, wherein the amount of copper (II)hydroxide is from about 0.1 mg/seed to about 0.21 mg/seed.

In some embodiments, a seed treatment formulation containing zinc as theonly micronutrient may be bound to (e.g. coated on or applied to) aspinach seed. In this embodiment, the seed treatment formulationincludes at least about 1.5 wt. % and no more than about 5 wt. % zincbased on the total weight of the seed treatment formulation. In someembodiments, a seed treatment formulation containing iron as the onlymicronutrient may be bound to a spinach seed. In this embodiment, theseed treatment formulation includes at least about 0.5 wt. % and no morethan about 3 wt. % iron, based on the total weight of the seed treatmentformulation. In some embodiments, a seed treatment formulationcontaining manganese as the only micronutrient may be bound to a spinachseed. In this embodiment, the seed treatment formulation includes atleast about 0.5 wt. % and no more than about 3 wt. % manganese, based onthe total weight of the seed treatment formulation. In some embodiments,a seed treatment formulation containing copper as the only micronutrientmay be bound to a spinach seed. In this embodiment, the seed treatmentformulation includes at least about 2 wt. % and no more than about 8 wt.% copper, based on the total weight of the seed treatment formulation.In some embodiments, a seed treatment formulation containing chromium asthe only micronutrient may be bound to a spinach seed. In thisembodiment, the seed treatment formulation includes at least about 0.5wt. % and no more than about 2 wt. % chromium, based on the total weightof the seed treatment formulation. In some embodiments, a seed treatmentformulation containing cobalt as the only micronutrient may be bound toa spinach seed. In this embodiment, the seed treatment formulationincludes at least about 0.5 wt. % and no more than about 2 wt. % cobalt,based on the total weight of the seed treatment formulation. In someembodiments, a seed treatment formulation contains at least twodifferent micronutrients, wherein the seed treatment may be bound to aspinach seed. In this embodiment, the seed treatment formulationincludes at least about 2 wt. % total micronutrient, based on the totalweight of the seed treatment formulation. Alternatively, the seedtreatment formulation comprises at least about 10 wt. %, alternativelyat least about 15 wt. %, alternatively at least about 20 wt. %,alternatively at least about 22 wt. %, alternatively at least about 25wt. %, alternatively at least about 30 wt. %, alternatively at leastabout 35 wt. %, micronutrients based on the total weight of the seedtreatment formulation. Alternately, the composition contains less thanabout 15 wt. %, less than about 10 wt. %, or less than about 5 wt. % ofboron, chromium, cobalt, copper, iodine, iron, manganese, molybdenum,selenium, sulfur and zinc, in combination, again with reference to totalweight of the seed treatment formulation. In each of these embodiments,the spinach seeds may be substituted with pea, forage corn, sweet corn,or soybean seeds.

In general, the seed treatment formulation comprises a chelating agent.Without wishing to be bound by any theory, it is believed that thecoordinated bonds of the chelating agent holds the micronutrient metalcomponent of the seed treatment formulation so that it remains readilyavailable to the emerging root system. As a result, uptake of themicronutrient metal by the emerging root system is improved leading toadditional strength and viability. Use of a chelating agent alsoadvantageously binds copper ion, maintaining the presence of copper ionin the soil and facilitating contact with undesirable fungal pathogens.

In some embodiments, the chelating agent of the seed treatmentformulation is zeolite, EDTA, or a combination thereof. In someembodiments, which are suitable for certified organic agriculturalapplications, the chelating agent of the seed treatment formulation iszeolite. In some embodiments, the seed treatment formulation compriseszeolite in an amount ranging from about 3 wt. % to about 10 wt. %, basedon the total weight of the seed treatment formulation. In someembodiments, the seed treatment formulation comprises zeolite in anamount ranging from about 4 wt. % to about 9 wt. %, based on the totalweight of the seed treatment formulation. In some embodiments, the seedtreatment formulation comprises zeolite in an amount ranging from about5 wt. % to about 8 wt. %, based on the total weight of the seedtreatment formulation. In some embodiments, the seed treatmentformulation comprises zeolite in an amount ranging from about 6 wt. % toabout 8 wt. %, based on the total weight of the seed treatmentformulation. In some embodiments, the seed treatment formulationcomprises about 3 wt. %, 4 wt. %, 5 wt. %, 6 wt. %, 7 wt. %, 8 wt. %, 9wt. % or 10 wt. % zeolite based on the total weight of the seedtreatment formulation. These values are significant in that amounts ofzeolite less than about 3 wt. % do not provide sufficient chelationeffect, while amounts of zeolite greater than about 10 wt. % may resultin phytotoxicity.

In general, the seed treatment formulation may comprise one or moreadditives serving various functions. For example, the seed treatmentformulation may comprise a binding agent for improved adherence of theseed treatment formulation to the seed, a humic acid source for improvedchelation (in addition to the chelation effect of EDTA or zeolite), asoil conditioner for improved micronutrient availability and uptake, andother additives that may confer a beneficial effect on the emerging rootsystem.

In some embodiments, the seed treatment formulation includes at leastone soil conditioner. Soil conditioners may be effective for stimulatingantimicrobial activity and improving growing conditions for the seed.One representative soil conditioner that may be employed is BorreGro CA(commercially available from LignoTech AGRO), a purified calciumlignosulfonate product. Typically utilized as a soil-based product, asoil conditioner for use with the seed treatment formulation is adaptedfor application to (e.g. binding to or coating of) the seed itselfrather than being deposited in the surrounding soil.

In some embodiments, the seed treatment formulation may comprise a soilconditioner in an amount ranging from about 0.5 wt. % to about 3 wt. %,based on the total weight of the seed treatment formulation. In otherembodiments, the seed treatment formulation may comprise a soilconditioner in an amount ranging from about 1 wt. % to about 2 wt. %,based on the total weight of the seed treatment formulation. In yetother embodiments, the seed treatment formulation may comprise a soilconditioner in an amount ranging from about 0.5 wt. % to about 1.5 wt.%, based on the total weight of the seed treatment formulation. Incertain preferred embodiments, the seed treatment formulation maycomprise a soil conditioner in the amount no greater than about 3 wt. %,at which point the soil conditioner may have a negative effect on theemerging root system as a result of toxicity.

In certain embodiments, the seed treatment formulation may comprise abinder component. The binder component of the seed treatment formulationmay be comprised of an adhesive polymer that may be natural or syntheticand is without phytotoxic effect on the seed to be treated. The bindermay be selected from polyvinyl acetates, polyvinyl acetate copolymers,polyvinyl alcohols, polyvinyl alcohol copolymers, celluloses, includingethylcelluloses and methylcelluloses, hydroxymethylcelluloses,hydroxypropyl cellulose, hydroxymethylpropylcelluloses,polyvinylpyrolidones, dextrins, malto-dextrins, polysaccharides, fats,oils, proteins, fiber gums including gum arabics, shellacs, vinylidenechloride, vinylidene chloride copolymers, calcium lignosulfonates,acrylic copolymers, starches, polyvinylacrylates, zeins, gelatin,carboxymethylcellulose, chitosan, polyethylene oxide, acrylimidepolymers and copolymers, polyhydroxyethyl acrylate, methylacrylimidemonomers, alginate, ethylcellulose, polychloroprene and syrups ormixtures thereof. Preferred binders include polymers and copolymers ofvinyl acetate, methyl cellulose, polyvinyl alcohol, vinylidene chloride,acrylic, cellulose, polyvinylpyrrolidone and polysaccharide.Particularly preferred classes of binders include polyvinyl acetates(e.g. for use in conventional growing) and fiber gums (e.g. for use inorganic applications).

In one embodiment, the seed treatment formulation may comprise a humicacid source, which functions as a complexing agent for soil nutrientsand maintains soil nutrients in forms that are more readily available tothe plant. In an exemplary embodiment, the seed treatment formulationcomprises humic acid in an amount ranging from about 0.5 wt. % to about3 wt. % of the total seed treatment formulation. In another exemplaryembodiment, the seed treatment formulation comprises humic acid in anamount ranging from about 0.5 wt. % to about 1.5 wt. % of the total seedtreatment formulation. In yet another embodiment, the seed treatmentformulation comprises about 1 wt. % humic acid based on the total weightof the seed treatment formulation. In certain embodiments, the humicacid source is substantially free of fulvic acid or fulvic acidadditives, which yields undesirable precipitates in the seed treatmentformulation of the present disclosure.

The seed treatment formulation is applied to the seed and dried to forma coating. The relative amounts of the ingredients in the formulationwill be the same as the relative amounts in the coating with theexception of the evaporated water. Any of the described seed treatmentingredients will also be ingredients in the coating.

The seed treatment formulation may be applied to a seed or population ofseeds by methods known to those of skill in the art. In particular, theseed treatment formulation may be applied to primed or unprimed seeds,with exemplary priming techniques including hydropriming, solid matrixpriming, drum priming, and the like. Primed or unprimed seeds mayoptionally be dried at a temperature ranging from about 80° F. to about110° F., to reach a moisture content less than about 50%, 40%, 30%, 20%or even 10%, prior to application of the seed treatment. The seedtreatment may be bound to the seed or population of seeds by any one ofa variety of seed coating methods, including drum coating, rotarycoating, pan coating, fluidized bed coating, and the like. In certainembodiments, treated (i.e. coated) seeds may be put through a seconddrying process to reduce moisture content of the seed treatment to lessthan about 25%, 20%, 10%, or even 5%. In some embodiments, the (primedor unprimed) seed(s) to which the seed treatment formulation is appliedmay be disinfected prior to application using one or more of hot water,warm/moist air, steam, 1% bleach solution, peroxyacetic acid, and thelike.

In certain embodiments, the seed(s) may be substantially encapsulated bythe seed treatment coating. In another embodiment, at least 95% of thesurface area of the seed(s) may be coated with the seed treatmentformulation. In yet another embodiment, at least 90% of the surface areaof the seed(s) may be coated with the seed treatment formulation. In yetanother embodiment, at least 80% of the surface area of the seed(s) maybe coated with the seed treatment formulation. In yet anotherembodiment, at least 75% of the surface area of the seed(s) may becoated with the seed treatment formulation. In yet another embodiment,at least 50% of the surface area of the seed(s) may be coated with theseed treatment formulation.

The seed treatment formulation is used to produce a seed coatingeffective to protect emerging root systems from fungal infection. Insome embodiments, the coating is effective to protect the emerging rootsystem from fungal infection for at least 7 days. By way of furtherexample, the coating is effective to protect the emerging root systemfrom fungal infection for at least 10 days. By way of further example,the coating is effective to protect the emerging root system for atleast 12 days. By way of further example, the coating is effective toprotect the emerging root system for at least 14 days. By way of furtherexample, the coating is effective to protect the emerging root systemfor at least 15, 16, 17, 18, 19, 20, or 21 days. The coating may beeffective to protect the seed from pre-emergence fungal infection,post-emergence fungal infection, or both pre- and post-emergence fungalinfection.

In certain exemplary embodiments, the seed treatment formulation isorganic (i.e. certified organic). For a seed treatment formulation to beorganic it must satisfy specific governmental standards. Thesegovernmental standards vary from country to country. The term “organic”or “certified organic” as used in the pending application is intended toindicate that the seed treatment formulation has satisfied the standardsfor being denoted as organic in both the United States and the EuropeanUnion. The United States Department of Agriculture (USDA) regulatesorganic certification within the United States through a NationalOrganic Program (NOP). To qualify to use the organic label, therequesting organization must be certified as satisfying a variety ofguidelines by an NOP accredited certification agency; for example,certification by Agricultural Services Certified Organics, LLC (ASCO).

While the present disclosure has illustrated by description severalembodiments and while the illustrative embodiments have been describedin considerable detail, it is not the intention of the applicant torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications may readily appear tothose skilled in the art.

EXAMPLES

The following non-limiting examples are provided to further illustratethe present disclosure. It will be apparent to those of skill in the artthat the techniques disclosed in the examples that follow representapproaches that function well, and thus can be considered to constituteexamples of modes for practice. However, those of skill in the artshould, in light of the present disclosure, appreciate that changes canbe made in the specific embodiments that are disclosed and still obtaina like or similar result without departing from the spirit and scope ofthe disclosure.

Example 1

The seed treatment formulation consists of the materials listed in Table1, which are incrementally mixed, over a period of several minutes, inthe indicated amounts to form a solution. The material is fully mixedfor an additional 30 minutes before application by film coating toapproximately 1.00 lb. of spinach seeds. The coated spinach seeds aresubsequently dried to 6-7% moisture content. In this example, while thecopper (II) hydroxide used is 77% pure, the weight percent of copper(II) hydroxide is 8.6%

TABLE 1 Wt. % Ingredient (Total Formulation) Water 71.4% Zinc Sulfate16.2% Lignosulfonate Soil Conditioner 1.3% Fiber Gum 1.6% Zeolite 9.5%Copper (II) Hydroxide (77%) 8.6%

Example 2

Randomized 60′ split plots were planted with raw spinach seeds (control)and spinach seeds coated with the formulation of Example 1 in acommercial organic field using commercial planting methods. All seedswere sown using commercial planting methods at a depth of 0.5 to 1 cm,in 48 rows on an 80″ wide bed at 3-4 million seeds per acre. Spinachvarieties Yukon and Castillo are shown in FIG. 1 (“CT”=castillo treated;“CR”=castillo raw; “YT”=yukon treated; “YR”=yukon raw), whichillustrates crop density 6 days after planting.

Image analysis of canopy coverage is shown in FIG. 2-7. Images shown inFIGS. 2-4 were taken using software comparable to ImageJ or Canopeo(iPhone-compatible app), with reversal of image color to enable pixelcount and subsequent area determination. As shown in FIGS. 5-7, canopydevelopment was significantly (P=0.05) faster with treated spinach seedduring first 2 weeks from sowing in both Callisto and Yukon varieties.Additionally, canopy area was significantly larger (P=0.05) and lesspatchy when treated seed was sown compared with untreated seed.

Example 3

Randomized 60′ split plots were planted with raw spinach seeds (control)and spinach seeds coated with the formulation of Example 1 in acommercial organic field using commercial planting methods. All seedswere sown using commercial planting methods at a depth of 0.5 to 1 cm,in 48 rows on an 80″ wide bed at 3-4 million seeds per acre. Spinachvarieties Yukon and Castillo are shown in FIG. 8 (“CT”=castillo treated;“CR”=castillo raw; “YT”=yukon treated; “YR”=yukon raw), whichillustrates crop density 9 days after planting.

Image analysis of canopy coverage is shown in FIG. 9-13. Images shown inFIG. 9 and FIG. 10 were taken using software comparable to ImageJ orCanopeo (iPhone-compatible app), with reversal of image color to enablepixel count and subsequent area determination. As shown in FIGS. 11-13,early canopy development was significantly (P=0.05) faster with treatedspinach seed. Treated Callisto and Yukon seed showed significantly(P=0.05) faster development during the first 10 days and 7 days,respectively. Canopy area development from treated seed showed moreadvantage at Halperin site (Example 2) due to higher soil-borne diseasepressure there in comparison with Chular trial site.

Example 4: Peas

Pea seeds coated with the formulation of Example 1, except the amount ofcopper (II) hydroxide was varied, were planted in clean, non-inoculatedpotting soil as a control alongside treated seeds planted in field soilwith known Pythium Ultimum fungal pathogen contamination. The seeds werecoated with three different rates (3 wt. %-15 wt. % of copper (II)hydroxide) in the formulation of Example 1. The seedling emergencecounts were evaluated on days 4 and 7 after planting. The number ofhealthy plants (no symptoms of basil root rot) were determined.

Rate 1 (3%): No efficacy observed, as indicated, only 1-2 plants emergedfrom the pathogen containing field soil.

TABLE 2 Example 1 formulation coated on Peas at 3% 4 DAP (16 seedsHealthy Wilt/Dead Treatment Soil Type Rep per rep) (7 DAP) (7 DAP) RawSunshine Mix Rep 1 10 16 Raw Sunshine Mix Rep 2 15 16 Raw Sunshine MixRep 3 9 16 Raw Sunshine Mix Rep 4 13 14 Example 1 Sunshine Mix Rep 1 1316 Example 1 Sunshine Mix Rep 2 13 16 Example 1 Sunshine Mix Rep 3 14 16Example 1 Sunshine Mix Rep 4 14 16 Raw Field Soil Rep 1 0 0 Raw FieldSoil Rep 2 0 0 Raw Field Soil Rep 3 0 0 Raw Field Soil Rep 4 0 0 Example1 Field Soil Rep 1 0 0 Example 1 Field Soil Rep 2 2 1 1 Example 1 FieldSoil Rep 3 0 0 Example 1 Field Soil Rep 4 1 0 1 DAP means days afterplanting

Rate 2 (9%): Example 1 formulation on treated peas at three times theactive ingredient concentration of rate 1 shows efficacy of the seedtreatment with 56%-87% of the seeds planted growing, producing anon-symptomatic healthy plant compared to raw non-treated seeds.

TABLE 3 Example 1 formulation coated on Peas at 9% 4 DAP (16 seedsHealthy Wilt/Dead Treatment Soil Type Rep per rep) (7 DAP) (7 DAP) RawSunshine Mix Rep 1 11 16 Raw Sunshine Mix Rep 2 12 16 Raw Sunshine MixRep 3 12 16 Raw Sunshine Mix Rep 4 12 14 Example 1 Sunshine Mix Rep 1 1314 Example 1 Sunshine Mix Rep 2 12 15 Example 1 Sunshine Mix Rep 3 12 16Example 1 Sunshine Mix Rep 4 11 15 Raw Fieid Soil Rep 1 3 2 1 Raw FieldSoil Rep 2 2 2 1 Raw Field Soil Rep 3 4 4 1 Raw Field Soil Rep 4 0 0Example 1 Field Soil Rep 1 14 13 1 Example 1 Field Soil Rep 2 11 14Example 1 Field Soil Rep 3 11 9 2 Example 1 Field Soil Rep 4 5 12

Rate 3 (15%): Example 1 formulation on treated peas at five times theactive ingredient concentration of rate 1 shows the negative affect ofthe high concentration reducing the number of healthy plants emergingfrom the fungal contaminated field soil.

TABLE 4 Example 1 formulation coated on Peas at 15% 4 dap (out of 16seeds Healthy Wilt/Dead Treatment Soil Type Rep per rep) (7 dap) (7 dap)Raw Lab Soil Rep 1 12 15 Raw Lab Soil Rep 2 14 16 Raw Lab Soil Rep 3 1316 Raw Lab Soil Rep 4 10 15 Example 1 Lab Soil Rep 1 10 14 Example 1 LabSoil Rep 2 12 14 Example 1 Lab Soil Rep 3 11 16 Example 1 Lab Soil Rep 412 15 Raw Field Soil Rep 1 1 1 Raw Field Soil Rep 2 0 0 Raw Field SoilRep 3 0 0 Raw Field Soil Rep 4 0 0 Example 1 Field Soil Rep 1 3 9Example 1 Field Soil Rep 2 2 8 Example 1 Field Soil Rep 3 7 7 Example 1Field Soil Rep 4 10 11

Example 5: Comparison with Cuprous Oxide

Pea seeds coated with the formulation of Example 1, at rate 2 (9% copper(II) hydroxide in the formulation), were planted in natural growingconditions for field peas in the Pacific Northwest. Pea seeds treatedwith Nordox, which contains cuprous oxide as the active ingredient, wereplanted in the same conditions. The pea seeds coated with theformulation of Example 1 produced 72% of the theoretical stand, whilethose treated with Nordox only produced 34% of the theoretical stand.

Example 6: Forage Corn

Forage corn was treated with three rates of the formulation of Example 1(Corn 4 at 4%, corn 5 at 11%, and corn 6 at 17%). Table 5 shows datafrom one rate. Samples 17-20 show that that non-treated corn seedplanted in field soil containing the fungal pathogen does not emerge andproduce a stand. In contrast, the corn seeds treated with formulation ofExample 1, Samples 21-32, have virtually the same number of plantsgrowing when compared to corn grown in disease free potting mix.

TABLE 5 Sam- Healthy Healthy Healthy ple Treatment Soil Type Rep (9 DAP)(14 DAP) (21 DAP) 1 Raw Peat Soil Rep 1 0 21 25 2 Raw Peat Soil Rep 2 022 25 3 Raw Peat Soil Rep 3 0 23 24 4 Raw Peat Soil Rep 4 0 25 25 5 corn4 Peat Soil Rep 1 0 21 24 6 corn 4 Peat Soil Rep 2 0 20 23 7 corn 4 PeatSoil Rep 3 0 11 25 8 corn 4 Peat Soil Rep 4 0 15 24 9 corn 5 Peat SoilRep 1 0 24 25 10 corn 5 Peat Soil Rep 2 0 24 24 11 corn 5 Peat Soil Rep3 0 12 25 12 corn 5 Peat Soil Rep 4 0 23 24 13 corn 6 Peat Soil Rep 1 024 23 14 corn 6 Peat Soil Rep 2 0 20 24 15 corn 6 Peat Soil Rep 3 0 2425 16 corn 6 Peat Soil Rep 4 0 20 18 17 Raw Field Soil Rep 1 0 1 6 18Raw Field Soil Rep 2 0 5 8 19 Raw Field Soil Rep 3 0 0 0 20 Raw FieldSoil Rep 4 0 0 3 21 corn 4 Field Soil Rep 1 0 20 24 22 corn 4 Field SoilRep 2 0 11 17 23 corn 4 Field Soil Rep 3 0 7 17 24 corn 4 Field Soil Rep4 0 4 19 25 corn 5 Field Soil Rep 1 0 14 22 26 corn 5 Field Soil Rep 2 021 24 27 corn 5 Field Soil Rep 3 0 8 22 28 corn 5 Field Soil Rep 4 0 1422 29 corn 6 Field Soil Rep 1 0 7 16 30 corn 6 Field Soil Rep 2 0 4 1631 corn 6 Field Soil Rep 3 0 18 23 32 corn 6 Field Soil Rep 4 0 17 21

A second replication of this trial with Corn 4, Corn 5, and Corn 6,treated rates of the formulation of Example 1 is shown in Table 6. Rawseed in diseased field soil not providing a stand while Corn 4, 5, and6, all showing improved seedling emergence as the seed treatment ispreventing root rot from occurring.

TABLE 6 Sam- Healthy Healthy Healthy ple Treatment Soil Type Rep (9 DAP)(14 DAP) (21 DAP) 33 Raw Peat Soil Rep 1 0 21 25 34 Raw Peat Soil Rep 20 22 25 35 Raw Peat Soil Rep 3 0 23 24 36 Raw Peat Soil Rep 4 0 25 25 37corn 4 Peat Soil Rep 1 0 21 24 38 corn 4 Peat Soil Rep 2 0 20 23 39 corn4 Peat Soil Rep 3 0 11 25 40 corn 4 Peat Soil Rep 4 0 15 24 41 corn 5Peat Soil Rep 1 0 24 25 42 corn 5 Peat Soil Rep 2 0 24 24 43 corn 5 PeatSoil Rep 3 0 12 25 44 corn 5 Peat Soil Rep 4 0 23 24 45 corn 6 Peat SoilRep 1 0 24 23 46 corn 6 Peat Soil Rep 2 0 20 24 47 corn 6 Peat Soil Rep3 0 24 25 48 corn 6 Peat Soil Rep 4 0 20 18 49 Raw Field Soil Rep 1 0 16 50 Raw Field Soil Rep 2 0 5 8 51 Raw Field Soil Rep 3 0 0 0 52 RawField Soil Rep 4 0 0 3 53 corn 4 Field Soil Rep 1 0 20 24 54 corn 4Field Soil Rep 2 0 11 17 55 corn 4 Field Soil Rep 3 0 7 17 56 corn 4Field Soil Rep 4 0 4 19 57 corn 5 Field Soil Rep 1 0 14 22 58 corn 5Field Soil Rep 2 0 21 24 59 corn 5 Field Soil Rep 3 0 8 22 60 corn 5Field Soil Rep 4 0 14 22 61 corn 6 Field Soil Rep 1 0 7 16 62 corn 6Field Soil Rep 2 0 4 16 63 corn 6 Field Soil Rep 3 0 18 23 64 corn 6Field Soil Rep 4 0 17 21

In summary, the data collected to date indicates that the seed treatmentformulation has a very strong efficacy against the soil fungal pathogenPythium. This has been demonstrated on leafy green vegetables speciessuch as organic spinach, field peas, and forage corn. It is believedthat the efficacy of this seed treatment will apply to other speciessuch as soybeans, which when grown organically are prone to crop lossesfrom this soil pathogen.

What is claimed is:
 1. A coated seed comprising: a seed and a coating at least partially surrounding the seed, wherein the coating comprises a fungicide, a micronutrient metal, and a chelating agent, the fungicide comprising copper (II) hydroxide, wherein the amount of copper (II) hydroxide is from about 0.12 mg/ seed to about 0.21 mg/ seed.
 2. The coated seed of claim 1, wherein the micronutrient comprises a metal selected from zinc, manganese, iron, boron, chromium, cobalt, copper, and salts thereof.
 3. The coated seed of claim 1, wherein the micronutrient comprises one or more zinc salt.
 4. The coated seed of claim 1, wherein the chelating agent is selected from the group consisting of zeolite and EDTA.
 5. The coated seed of claim 1, wherein the coating further comprises a binding agent.
 6. The coated seed of claim 5, wherein the binding agent is selected from the group consisting of a fiber gum and polyvinyl alcohol.
 7. The coated seed of claim 1, wherein the coating further comprises humic acid.
 8. The coated seed of claim 1, wherein the coating is substantially free of added fulvic add.
 9. The coated seed of claim 1, wherein the coating further comprises a soil conditioner.
 10. The coated seed of claim 1, wherein the coating further comprises a bactericide.
 11. The coated seed of claim 1, wherein the coating has a pH in the range of 6.0 to 6.4.
 12. The coated seed of claim 1, wherein the coating encapsulates the seed.
 13. The coated seed of claim 1, wherein the seed is a spinach, pea, or corn seed. 